I still prefer the Windows Live Mesh method. You get copies on each machine then. I've got it running on my fileserver too, which I've set to make backups at certain intervals during the day.
Putting it all on a NAS is putting all your eggs in one basket, a basket that needs other computers to access it!
Putting it all on a NAS is putting all your eggs in one basket, a basket that needs other computers to access it!